Storage replication is a data protection strategy in which data objects (e.g., files, physical volumes, logical volumes, file systems, etc.) are replicated to provide some measure of redundancy. Storage replication may be used for many purposes, such as ensuring data availability upon storage failures, site disasters, or planned maintenance. Storage replication may be managed directly between storage systems, such as storage arrays, in an approach referred to as storage-based replication or array-based replication (ABR).
Consistent replication across multiple storage devices, such as LUNs (logical unit numbers), has been traditionally implemented by storage system providers by sequencing write IOs across the storage devices. A group of consistently replicated storage devices is known as a consistency group (CG). CG-based approaches to ensuring replication consistency across multiple storage devices, however, require an extensive upfront effort to setup CGs ahead of time. In addition, the number of CGs that can be defined has a limit (on the order of 10's of groups) imposed by the storage system provider. Accordingly, there is a need in the art for more flexible approaches for consistent replication across multiple storage devices.